Method of and apparatus for making castings and handling and conditioning the molding sand therefor



A.hm'e 30, 131 M. sKLovsKY 1,812,121'4 METHOD oF AN APPARNTUSFOR lMAKING CASTINGS AND HANDLING AND G0 TI-ONING THE MQLDING SAND THEREFOR v Filed Aug: 2, 1926 7 Sheets-Sheet 1 June 30. 1931. M. sKLovsnY 1,812,121-

METHOD OF AND APPARATUS FOR MAKING CASTINGS AND HANDLING AND CONDITIONING THE MOLDING SAND THEREFOR Filed Aug- 2, 1925 7 Sheets-Sheet 2 1,812,121 I AND HANDLING A REFoR June 30, 1931. M. SKLOVSKY METHOD 0F AND APPARATUS FOR MAKING CASTINGS AND CONDITIONING THE MOLDING SAND THE Filed Aug. 2, 1926. '7 Sheets-Sheet 5 W///wA/A@ ma A@ ,w

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M. SKLOVSKY June 30; 1931.

1,812,121 NGs AND HANDLING lVlETI'IODv OF AND APPARATUS FOR MAKING GASTI AND CONDITIONING THE MOLDING SAND THEREFOR Filed Aug. 2, 1926 7 Sheets-Sheet 4 June 30, 1931. M. sKLovsKY METHOD OF AND APPARATUS FOR MAKING CASTINGS AND HANDLING AND CONDITIONING THE MOLDING SAND THEREFOR 4 Filed Aug 2, 1926 7 Sheets-Sham; 5

SNN NNN AGN Q u@ @SNN N q, NESS Jne'30v4 1931.` M. s'KLovsKY v RATUS A FOR MAKING CASTI D ONING THE MOLDING SAND Filed Aug. 2, 1926 METHOD OF AND A AND CON IIIIIIINH :w|x mwN www@ June 30, 1931. M. sKLovsKY METHOD OF AND APPARATUS FOR MAKING CASTIN vAND CONDITIONING THE MOLDING SAND THEREFOR Filled Aug. 2, 1926 //////NMNU// YPatented June A30,1931 f l Mniironornnn API-fanarts non i/rAKINcf` oAs'rIiTGsAND lmainmise Min f coNnrTIoNING THE MQLDING SANDPTHEREIOR' 1 o, f

-. faplngation mea Aug-asta, i926. :serial-Numana '1 The present `invention relatesto metlfiods of .and apparatus for making castingsga-nd handling' and conditioning the molding sand therefor. I j

p 5 The inventionaims broadly Lto providean improved method of "and: lpparatus for n making castings by a continuous casting.

process,y and` also. aims Vto provide kan im- @proved method: ofand apparatus for .han-

'. :iD .dling andlgconditioning fthe sand used in this frastingprooess. I

j The continuous: casting cycle involves: -1irst,- forming the molds at arnold ysetting'for forming zone; trar'lsiferring the `molds to'A al ,f f, 'l5 revolving pouring tableU in .close proximityA thereto,` on Which Ytable the molds algerina-ifn-k :tained in continuous movement during thel ypouring of ythe .metal :therein and during the cooling othe'inetalin'the moldsg'returning '26 ethe molds blytheinovemfe'lrt ofthe table to a r f :dumping Zone v.preferably in close' vproximity y:to theunold forming zone; lifting tlieinolds i Y Vfrom the .table atthsdumpulg fp'ontand opening and 1dumping:y kthe flasks. thereof 25a* andlinally freturn-ingthe rempty -lasks Lto` theV mold "formi-ng Yzone for the making of `new molds -forfa repetition loi this same'cycle...

, Numerous advantages, ffollow :from `the rapidity ,With-Which this cyolefCa-n be Acomf3,0 fpleted. Generally the time ,interval Will'def' -pend upon lthe time vrequired for thecomple- `tion of the longest ,step 'inthe cycle, which Will vary considerably With- ,th'el lliflnt sizes and shapes of thefarticlesztofbe cast. As illi'istrative of the results "attained one Yinstallation which ll. have built `for the :casting of :wheels for mowing' machines, cto., the eno t tire cycle, from the ltimethat tlie-mrolls are; v"filled v`with f sand' `to jthe time When ythefemptyf rlasll-:s are returned vtol this mold KVforming Zone, 'is coinpletedin approximately twenty f minutes.

ISeveral advantages are obtainedby this continuous method of casting. The Iinvest-fr' ment 'in lmold liasksismuch' smallerasronly a few flasks are required; for example, in thel installation referred :to` above,gappr'oXi- .-'mately lfifteen or rtwenty' .c ompletergmolds suffice -for--the lmaking of several hundred '59 i ,mower lWllelfs per day. *'lfhe; space require# ivIoLlIN'Ef ILLINOIS, ,AssIeNoR mo ,nanna afeoMPANx or. mornin,

ILLINoIsAcoBroRATIQN 0FfILpIN01S ments for carrying on thismethod of'inalririgl Y entire day?soutput are lirst formed in'preparation yfor tthe one pouring operation ,of fthe @the individual Workman waiting .for .particular duties, inasmuch' as each step Qrduty lis being continually repeated inthis continuous .casting process. Finally, the gross outputin day. Furthermore, rthere is yless-time lostfbyffy tons of castings, fcomputed upon .the -basisof i j space and'labfor is much `higher With thiston-Y tinuous casting process. l

One factor Which'jhas `made thiscontinuous 'casting` process feasibleis thek method j .of handling and .properly conditioning the molding sand.` i The present :method .of han e dling and Vconditioning .the sandpinvolves a continu0useyo le, similar rto thecastingprocfess, foperatlng fupon `the theory .of yutilizing arelatively'.k small -yolume of .sand and cir-y culating uitV continuously through al closedv .,@yelefwherein occurfcertainrConditioning:and

handling .steps which quickly prepare .the sand for each subsequent use.--By virtudof fcertain improvements in the steps and in thel Y f apparatus which Ieinploy in this-Sandton Aditioning cycle, the .sand` 'can bereeonditioned` inv a' comparatively shorttimeg illustrative of ithe rapidity of this;operation ,If again refer to the installation mentionedv labove wherein thesand makes a completelcirf cuit.,=thro`ugh lthe conditioning portionxofjgits Y i cycle in about l the same length ofv time requiredg-for theeonipletion of one casting op- .lThe present process avoids the long tir'ne-'in-v vimethods of yconditioning' sand;` For` exam- :eration kviz',approxiinately twenty -minutesQ-J l tervalf-and-otherobjeetionsinherent in prior v flitnlrS.` ,rllhisfgenerally lmeans that thesan'd '.LJcan-only beus'edonce or-jtwice.each-dayand iheneefrequir'esthat a relatively llarge volume of this conditioned sand be availablefor-the.'Eml Y l A een??? ydfya A,ifflng operations. .The Vspace occupied by such sand, either on the molding floor or in overhead bins is a decided objection. Moreover, when the sand is reconditioned and allowed to remain in mass quantities in this manner there a tendency for the sand to pack and losc its desired looseness. There the sand is contained in bins or hoppers this tendency to pack often results in the sand bridging over in the chutes or other conveying means., involving delay and irregularity of delivery to the molds.

According to the present method of conditioning the sand, all the sand in the system is conveyed through the conditioning cycle in a relatively thin stratum or stream and is subjected to uniform treatment so that uniformity of condition of the sand is obtained and in a comparatively short time.

Referring now to the accompanying drawings wherein l have illustrated an embodiment constructed and operated substantially in accordance with the installation previously referred to:

Figure 1 a vertical sectional view through upper and lower lioor levers of a foundry building, illustrating tl e relative positions of the Vseveral pa'r s entering into the present methods and aiiiparatus.

Fig. 2 is a. plan view of the apparatus which is located on the molding floor.

Fig. 3 is a fragmentary sectional view through a portion of the pouring tablofor illustrating the details thereof.

Fig. l is a view partly in elevation and partly in section, illustrating one of the rollers for supporting the pouring table.

Fig. 5 is a. fragmentary vertical sectional View through the dumping hopper, the conveyingr belt and the rotating screen of the sand conditioning apparatus.

Fig. 6 is a detail sectional view taken on the plane of the liuc G of Fig. 5.

Fig. 7 is similar sectional view taken on the plane of the line 7-7 of Fig. 5.

Fig. 8 is a plan view of the dumping hopper. rotating screen and sand conditioning unit, a portion of the top tray of this sand comiitionin unit being broken away.

Fig. 9 is a vertical sectional view through the rotating sand conditioning unit. taken substantially on the plane of the line 9-9 of Fig. 8.

Fig. 10 is a detail sectional viewthrough two of the sand conditioning trays for illustrating the details of the rotary mixing devices.

Fig. 11 is a fragmentary plan view taken directly above the plane of the lower conditioning tray, for illustrating the conveyor chamber into which this tray discharges, and

Fig. 1.2 is a longitudinal sectional view through this conveyor chamber, taken approximately on the plane of the line 1212 of Fig. 11.

Figure 1 illustrates a typical installa-tion of my improved apparatus. In this installation, the apparatus is located on two different floor levels, the upper floor line being indicated at 16. ln this arrangement, the operations of forming the mold, `pouring the metal therein, and opening and dumping the mold are all performed on the upper floor level, this being referred to as the molding floor. The remaining apparatus for screening, tempering, cutting and conditioning the san d is supported on the lower floor level, this being referred to as the conditioning floor for the purposes of the present description. The sand conditioning apparatus is preferably disposed directly below the aforesaid apparatus on the molding floor, substantially as illustrated. Such is the preferred manner of disposing the component parts of the system, inasmuch as by this arrangement the conveying of the sand through the different steps of its continuous cycle can be simply and easily performed. For example the gravitational feed of the sand from the upper floor level down to the sand conditioning apparatus on the lower iioor is of advantage as it simplifies the handling and disposal of the sand dumped out of the flasks; and by such arrangement the excess sand which overflows the `flask or is stricken olf the flask in the mold forming operation is automatically returned to the system by gravitational feed. However, while this two level type of installation is preferable for the foregoing reasons, where space does not permit such type of installation, all of the apparatus can be disposed on the same or staggered levels Without sacrificing the more important advantages of the invention.

To facilitate the understanding of the apparatus and the several steps involved l shall first describe the path and steps involved in the movement of each flask or mold, and thereafter shall describe the path or circuit of the molding sand, making brief reference to the functions of the several parts as they occur in each of these cycles, In a later part of this specification l shall describe the component parts in detail.

The molds are first set or formed by a molding machine or machines located at a mold forming zone indicated at A in Fig. Q. rlie cope flasl; is indicated at c and the drag flask is indicated at el, both of these flasks boinc' filled in any suitable manner; in this instance a single stationary type of sand projector of the Beardsley-Piper type is shown for purposes of illustration.

After each flank is filled it is hooked or otherwise connected to an individual hoist 1.7-18, one being provided for each flask. One hoist has trolley mounting o-n the rail of a pivot-ally swinging iib crane 19. The other hoist 18 has trolley mounting on a. rail 21 which may have swinging movement or which maybe stationary. The outer ends of Y 3oM having anindividu-al'hoistE andicontriol mechthese overheadV rails *19 'andi 21T extend over the edge'oiiVr arotating?.pouringiable 22, .and the copeand diaglasks are carried'outlonltlie hoists* trave-ling fonj these rails and deposited -onthe edger offthis pouringtable.y lAtj such .time ther iiaskslare properly# assembled, the Svvinzf'jringV movement ofi' the jibfcranei'rlfpermitting thecope flask tofloemoved laterallyv for placing thel same "urmiiftheA dragfflask. Y Thehoists -lfT-JB arefthen releasedafnd rolled 'Y back -to lthemol-ding machine inL readiness to receive thefneXt-fpair of'flasks* y 1 'The loading -poi-nt Whe-retheiasls are as'-V sernbled and?A loaded f on `the pouring. talfilel is 15 indicated atlB, andv fromlthis lpointthe flasks arerevolvedaround' toaa pouring zone Gi.

' rammer intotheflaslvs. f Directly below the f grating' 32 vis alhopp'er through the lower f Vpaxrtof which travels a Vconveying beltf.37..j This belt conveys theV 'sandV finto the'smallgend f of. aj taperedpolygonal screen "38 ,which is continuously rotated. Herethej sand `is tumbled andshaken up in its action of'droppingk down fromeside to side oi'v'thisy polygonal Vscreeng'As the sand` is' .loosened `it is sifte-d V:down through the screen uponthe upper shelf l kontray of a'sand carrier 39.;- This device per- 1l I forms fthehseveralfunctionsy of 'cutting the y sand ,"tempering thesan'd and'maintaining a reserve accumulation of sand:` for meeting Supported abovethe pouring table is* a 'jib llcrane 24, the innerpivotedfendof vvliic-liis jourfn aled lfor swingingV- motion abouti-a vert'i- 20' cal-'axis substantially:coincidentiwith the axis otthepouring table.l 'The outerend of this jib 'crane tracksl on' a circular overheaditraek or rail 25. At one pointof its' angular movement, the jib'crane 2421"egisters'-vvithanfover furnacefrom vvhicli'l is drawn itlije 'molten nieta-l. The ladlesf'carrying "this molten metal i are" supported on trolleys-adapted* to l roll on this overhead track` system, 'each vladle anism whereby-it may loe;l rlaisedf'and lowered Vrelative to its trolley, 'aln'd tipped? to pour its Contents intoth'er mold eeroneiof these` ladleshasbeen runron ftothejib' crane 355-24', the crane* is swungtohljringthe.ladle into 'pouring'registryWith the spru-efliole'sfof eac-h on alA co'mmonf supporting sft-andardwith-the pouring table, 'the rotationalf motion ofi-the 40; pouring table 22 Avvillj tend `tol'swingjtjli'ef j'ib crane 2liv \'vitl'1`.-fit\', thereby facilitating' the pouring off'the niet'al intoeaclrofAthe'molds. The ib cra-ne,- can of c.ourse,be `svvung-1 ahead or loa-cli of' themotion'o'f' tlie pouri'ngvtable '-.451for filling nniltiplieity ofmolds. "Grenerally, about five or' six moldsvvould be pouredfromione ladle. Y `f The dumpingzone, Where the molds are lifted voili.' the pouring tablezanddiunpe'd, is

i 5o indicated at-'DiiniFigurel 2dl 'Eherot'ation oflthe table k22 is comparatifvely slow. sogthat c byv ther timeV the moldsl'have reached' this dumping zone -Vltle. castings' are4 suiiieiently cool toebe'removedfrom tlie niolds "Ati this veying mechanism may' be' employed;- After V the sandh'as beenf'dumjoed from bothiasks, n

these 'fiasksyare placed onfthe forward end -f pivoed therebetween to deiine'aslopingreon# 5 veyorsurface.l Thefmolder liftstheseflasks. f 'l l from the conveyogplacing the cope and ydrag *flasksfon vtheirV properl supports', previously described and again lills theselasls 'for arrep- K v-'etition-'of thecycle justjdescrihed.. 1 v,

I' 1I shall now describethe"circuitfthrough vwhich VtheV sand passesy from the point vvliere vit' isdumped through the! grating132to the pointfwhere .it is discharged from the sand fluctuating demands. vrIhe unit comprises a .myA

series yof vertically 4spaced*circular"traysor shelves which are rotatedsimultaneously, .the

sand being Worked and conditionedonl these Y "shelves and being dropped progressively rom one shelf bto the next. Thewater forcondr,

tioning thev sand is projected through a-sprinkler'heardllll located above-theV upper' shelf l' y' .and dis'chargin'gzvvater uponjthesand as itfis'i vsifted doWnuponlthis upper yshelf from= the rotatingscreen- 38.1 yTheis-and'contained kon each shelfis cut and turned overby a pluA -rallity `of rotating 1 mixing devices Vindicated generally at 42 -in'Figure 9. 'These mixing devices also have the actionoffworking. the sand'iprogressively inwardly or outwardly Y across the face of each shelf` for discharging thesanddownkon to the 'neXtvlovver shelf.

`That isA to say,infthe.case of one shelf or tray j -fthe 'dischargev` Will be from-.the outer periph# `1 ery thereoffdown on tothe nextl tray, and for this shelf the mixing deviceslvvill Work the sand Vfmtwvafrdlytoward its outer-periphery. fThe nextlovver tray Will'be arranged to discharge the san d fron'i'its inner periphery,and

-inlthe casef'of this tray `thezmiXing devices will progressively Work the? sandl inwardly n Itoward-its innerperiphery. This'invvard land outvvardfn'ioving anddropping offthe sand f from onetray tolanot'her continues downto Ls 'the bot-tomtrayWhere thesand 1s wiped orr 1 I raked vfronr the outer peripheryV thereof into a conveying'chamber 44.*' Such dischargeo' `Y I the lsandfrom the'lower shelf or trayis effected `by "a rake l5 illustrated.,inFiguresy 11 Lit and 12. This rake may be made adjustable and its positions may be controlled by the melder or his ant at the mold `terniiug zone A to regulate the volume ot sand supplied to the sand rannning machine. Contained within the conveying chamber 44 is a rotary sand impeller 46 (Figures 1l and 12) which is located in the lower part ot this chamber and which whips or throws the precipitated sand down into the lower boot 47 of a bucket conveyor 48. rlhis conveyor carries the sand up through a conveyor casing 49 and projects it down into a vertical chute 51 (Figure 1), from whence it falls into the hopper or spout 52 of the sand ramming machine 53. This sand ramming` machine preterably has an articulated arrangement of arms by which the sand projecting outlet oi'i the machine can be swun to project the sand .into any part of either ot the 'liasks c or (Z.

The supports on which these two flasks are mounted tor the operation ot filling the same, are placed over a grating` 54 formed in the Vfloor 16, as best shown in Figure rlhe grating is directly above the upper tray or shelll of the sand conditioning unit 39 on the vdoor below, and consequently any excess sand which is spilled over or struck oft the flasks can drop directly on to the top tray oit this sand conditioningunit 39 and again pass through the conditioning cycle tor redelivery to the sand ramming machine 53.

I shall now describe each oi the parts .in detail, taking up the same in the order in which they occur in the foregoing cycles of operation. v

The hoists 17 and 18 and the j ib cranes 19 and 21 are devices well known in the art and need not be described in any detail. The crane 19 has suitable pivotal mounting on an overhead support above the gravity conveyor 34. lts other end carries a roller 56 which tracks along an overhead supporting rail 57 curved substantially coucentrically ot the path of movement of this crane. Each hoist 17-18 has a trolley rolling along the horizontal rail of the crane, and the hoist may be either power or manually operated.

The pouring table is illustrated in cross section in Figure 3. It comprises a disklike table top 58 ol wood or metal. lhe outer edge ot this table is 'faced with a ring 59 of angle bar cross section. The upper flange oli this ring rises above the top of' the table disk to conline a bed ot sand 6l on the disk. The sand .terms a suitable matting which may be struck ott to form a level resting place -for each mold. Such bed ot and also aids in cushioningl the mold against any vibrations which might b set up in the table. lt desired, an inner ring 62 may be secured to the top oit the table to define an annular space between the outer and inner rings 59 and 62 for receiving the sand` matting.

The disk is secured upon a structure oi: any

suitable form, built up of channels or angles 63 joined together in a circular or polygonal trame. Secured to the under side of this trame structure, at the center thereof, is a spherical bearing socket 64 comprising upper and lower socket sections: 65 and 66 joining on a horizontal diametrical plane passing through the socket. Engaging within this socket is a ball 67 supported on the upper end ot a standard 68. The lower socket section is secured to the upper socket section7 after the mounting ot the ball therein, by screws 69 which hold the ball therein and which prevent any upward movement ot the table relative to the ball and its standard 68. This standard is supported in a pedestal 71 consis ingot' two clamping halves which are bolted together over the standard. The standard has a. key slot 68 therein for receiving a key carried by the pedestal 71, whereby the standard and ball are held against rotation. The pedestal 71 is suitably anchored to the floor 16.

A circular rail 73 is bolted to the under side of the fra-me 63 in inverted position, this rail.

rolling on a plurality of rollers 7 4 supported at circularly spaced points under this rail. As shown in Figure 4, each of these rollers is journaled between the side` arms 75 of a forked yoke 75. One end of this yoke is pivoted at 76 to the stationary base plate 77 and the other end carries an arrangement ot adjusting and clamping screws whereby the yoke may be raised or lowered to adjust the height of the roller 74. As shown in Figure 3, a central adjusting screw 78 threads down through the free end of the yoke and bears against an abutment surface at the end of the base plate. T wo clamping screws 7 9-79 pass loosely through this end ot the yoke and screw into holes in this abutment surface t'or clamping the yoke in any adjusted position. Antifriction bearings 81 of ball or roller type are interposed between the roller 74 and the journal member 82 carried between the side arms of the yoke. Removable cover plates 83 may be secured to one or both sides of each roller t'or confining the anti-friction bearings therein and tor preventing the ingress of dirt or sand. rlhese rollers carry all of the tipping pressures to which the table may be subjected because of uneven loading. Preterably7 these rollers are adjusted so that they will also carry the entire weight of the table and its load, thus relieving the ball and socket center bearing ot this duty, whereby this ball and socket bearing will only serve to center the table.

Secured to the under side of the table outside of the supporting rail 73 is a circular rack 84 of channel cross section, having` its rack teeth 84 facing downwardly. Pairs o'l lugs 85 projecting laterally trom this rack at spaced points receive bolts 86 by which the rack is secured to the frame structure 63 ot l 49 eration can stand on the 'rotating-table. 11i-1r With a. table.L

the. table: The table lis/preferably. driven through aniindividual electric motor y posed vincloseproximity to thetableand ,pref Q erablysata pointl removed from: the loading". and'dumping zonesBfand D Where itjfwill not interfere Withthese operations (seeFigshaft ofl the gear reducing l'unit I 8,8' carries a .pinion 92 lvvhi-eh meshesiwith the rack teeth.; 811. In the installation vWhich*Lliaveeonf st-ructed for theicasting of mower lvvhee'ls the tab-1e is designed to carry approximately 14 large..rnolds,v each approximately lforty-(tvvo f inchesin diameter, and thetable is rotated ata-speed of approximately one revolutionvr i everyiifteenor twenty minutes.

"shown, approximately five *of itliese InoldsLV 45 Will befilledfroni `the .ladle at'one pouring any suitable power operated vtype.employingV yeo .zoneDrcorI-esponds,to a co The pouring crane v24,' is suitably svviveled to an overheadsupport 93' forl swinging mover` ment substantially axially of 1 the talole`22. 'llhe swinging end'- of the cranev is'provided'` With-one ormorerollers 941 which roll on the inner flangeiof the Curved track 25; This lattery track is supported a considerable dis- 1 tanceabove the table by any suitable support#` ing` framework 95. -f 1n one positionthepouring'. crane-24ialines Vwith the. overhead track 26:W-hich leads out to the cupolav as previously described. After fillingv'atthewcupola the. ladles maybe brought'back to-.thistrackQ on:` a spur tracksection 26" which; canvloe .switched over into "registry with theA main track sec-tion.` for continuing` the` travel vofthesere'lled ladlesup to thepouring table. The'worklnan performing the pouring op'- side ofi the circle of' molds. constructedto VVcarry thenuniber of'molds operation, andf hence ythis pouring( Zone Will embrace: Yapproxiiinately-` one-third of `Ythe travelv of the moldsfion the table. The re.- inain'ing path of travel up'to the dumping the metal has'opportunity tocool. u i

The hoisting device 28 for lifting the molds off' the table at the. dnmpingrpointl) isof either compressed air or electricityffor 'its operation',v This hoist may 'be `suspended from atrolley 97 rolling along theztransjverse rail 98of the 'carriage- 29;V The movement of Athis carriage along the -overheadgrails 3 1f 1' will7 enable theho'ist 28 togvbein'oved Vfor- Ward-lyV or outwardly in any i direction i from the table,V Wherebythe hoist-can `be connected to a moldat any-.point in this dumping zone D; As before described, the mold islfted from thetablebythis hoist and the flasksV veyor beltto pass throughthe bottoni-of the` e hopper. `Tvvov or. more "rollers-1107 arej'ou'rg' oling Zonein vvhichthrough the, graiag.- Y e tion/aly construction', this A. conveyorA beingf sloped, down to and curved around inbackof`1 spaced .relation "passing'tiefrods kk10,5

throughalined holes in these bars, and' interv-` posing 'spacingsleeves 106bet'vveen the bars,

,sf j

dumped. to discharge;.theifloontainedi Y The gravity. Conveyor; 34:` is of"l i 00111762115 i i' r'angle brackets 101ysecured inthe manginaliYr frame;10,2. The bars 103 are-maintained in hopper 36'is rivetedorbolted to the marginalV frame 102l belovv the grate bars 103, this hop-V conveyor belt 37'.v The ends of the liopperfaie left,openjadjaoentthefbottomlthereof toper-` Y Initthe upper-and lofvver flights 'of this Con' naledonrfshhafts ,1085extending between the` side Wallis of the hopper. These rollers sus-'f i' tain'the5upper stretch of the belt'37and the f Weightof ythousand siipportedthereonf@ i armature shaft ofan eleotricymotoill. As shovvn'in Eign're 1, the opposite end"` of the Conveyor beltv V37g Wllioh'V extends out through *the 'reary end of the hopperi36is passed around 122 heldin' spacedrelationtodefinej the perimeter of the;devicebyibrackets 123which are screvvedto the inner sides of these barsv f f Thedirectionof travel of the up'per.stretfh` .of the belt is'tothe right tovvard'sthe shaking screen 38,vievv edin Figure 5. 'e Extending Y.

frornthe (,)peiliiigv 109 atrthis end; of the 'hop'- v per is a troughlll which serves to confine the y.

Y the -molclingmachiiies foredisp'ojsing the flasks; .4 in Vco n'venient position for the-melder to lift"v e and place'upon the supporting standards for; ltheseiasks."' 7 l 32 Qissupported in anopening 101'1n the ii-oor;v 16,.this opening being marginallyfacedb j fan,A yangle',l iron frariieflOQ.k The grat-imgv Pile .erablyfvcoinprises afseries e of'bafrs '103 having u 105|' vsand carriedon the beltlandyto ,preventtlfieg loss of anysan'd spilling off Vthe edgesv V0f the "beltj,V Thistrough isextended up togtheinlet.:l

endof the revolving screen 38, the beltv 37 Apassing over a roller 112 `at this;pnintjA f n projeeting the vvsandr into thescreenu,The n A'shaft' 113 oinavhichfthifs latter yroller is meunt ed Vextends through openings'inthe sidewalls i of thetrough 111.,an/d. has bearing support inbearingsjcarried bya frana evhorkfV 1141 'sup-'-iY ported directly below the'up'per floor 16.vv One end of this lshaft oarriesa large Vbelt f yvvheelllv overffwh'ichtravels lojeltllfeX` c tending toa belt pulleyl 117 mountedon'the w QS f and which are fastened at their inner ends to flanged hubs 124 mounted on the axial driving shaft 125. The bars 122 diverge out` wardly toward the right hand end of the screen, as viewed in Figure 5, to give the screen a tapering pitch. The wire screening 126 encircles the outer sides of these bars and is held in place thereon by having its ends clamped between inner and outer bars or sections of strapping 127-128 bolted to the supporting bars 122. At the inlet end of the screen, the bars 122 are turned outwardly and are fastened to one side of a supporting ring 129. This ring 129 has a central flange which tracks in the grooved peripheries of two supporting rollers 131 carried in bearing brackets 132 secured to the frame work 114, as shown in Figure 7. The tension of the wire screening 126 around the spaced supporting bars 122 gives the screen a polygonal cross section, and by virtue of this and the tapered form of the screen the sand will sift through the screen or gradually work downwardly toward the-.large end thereof until the lumps too large to pass through the mesh of the screen are broken up sufficiently against av retaining ring 132 to permit the sand to sift down through the screen. j

As shown in Figures 1 and 8, the driving shaft is supported in a bearing 134 mounted on the framework 114, and beyond this bearing the shaft is connected to a speed reducing unit 135 through a coupling 136. An electric motor 137, mounted on the framework 114, is connected to this speed reducing unit 135 through a coupling 138. The framework 114, supporting the conveyor belt 37, the rotating screen 38, and the driving appurtenances for both of these elements, is preferably supported independently of the molding floor 16 so that any vibration set up in this framework 114 will not jar the molding floor.

The sand sifting down through the rotating screen 38 drops upon the upper surface of the sand carrying and conditioning device 39. As before described, this device comprises a tier of shelves or trays on which the sand is intimately mixed for securing the proper tempering and cutting thereof. In the construction shown, there are seven of such shelves or trays 141 and 142, although this number may be increased or decreased Q as desired. The upper tray 141 is continuous across its entire surface for Areceiving the sand sifting down through the screen 38, and the sand precipitated down through the grating 54. This top tray is arranged to discharge its sand from the outer edge thereof, and hence the second tray 142 is extended slightly beyond the outer edge of the upper tray to receive the sand dropping from the upper tray, the outer edge of the second tray f' having an upwardly turned lip 143 for preventing the sand from falling off the outerV the third tray 141. This and the succeeding trays alternate in the arrangement described of the first and second trays, whereby the sand is alternately dropped from the outer periphery of one tray and from the inner periphery of the next succeeding tray. The sand drops upon the inner portion of the bottom tray 141b and is discharged from the outer periphery thereof into the conveying chamber 44, which l shall hereinafter describe in detail.

Figure 8 illustrates one construction of framework for these trays. Each tray below the top tray 141a preferably comprises a series of segmental plates 145 which are riveted to radially and transversely extending angle bars 146 serving as a supporting structure for the tray. The several trays are held in spaced relation by vertically extending bars 147 arranged circular-ly in the form of a central cage. From each tray or shelf 141 an annular wall 148 extends upwardly to a point above the level of the next succeeding tray 142. This wall prevents the sand which drops from the inner edge 144 of the upper tray, and which accumulates on the lower tray 141, from moving inwardly beyond the range of the mixing devices 42. A deflecting skirt portion 149 is secured to thc upper edge of each of these annular walls and extends downwardly below the frame bars of the tray for deflecting the falling sand outwardly on the lower tray 141.

The entire unit is supported and rotated in substantially the same manner described of the pouring table 22 of Figure 3. The unit is alined by a ball and socket joint interposed between the frame members of the lower shelf 141) and the lower floor level 151. This ball and socket joint comprises the upper socket portion 64, the ball 67, mounted on the standard 68 and the pedestal 71 for supporting this standard, all substantially the same as described of the ball and socket The mounting for the pouring table 22.

weight of this sand conditioning unit and its load is carried on a. rail 73 revolving over adjustable rollers 7 4, as previously described, and the unit is revolved through a depending rack 84 with which meshes a pinion 152. This pinion is driven from an electric motor 153 through a speed reducing unit 154, both mounted on the lower floor level 151. The .shaft of the motor 153 carries a pulley 155 over which travels a belt 156 passing up to a large pulley 157 on an upper countershaft 158. From this countershaft a belt drive is transmitted to all of the mixingl devices 42, as l shall presently describe.

As shown in Figures 9 and 10, one of the mixing units 42 is provided for each tray rentree 1414-1412,', the shaft of each mixing device#V Vextending radially inbetvveen upper and low#V er trays."4 These Ymixing devices yare practically all identical andy the ide'scripltion of onevvill sulhce'vfor` all: `Each mixershaft 161;y is ournaleda't its outer end 1in a bearing supported .between *vertically 'extendingjk vframe 'membersg163-' `'The inner endl of 'ea'clhf shaft is supportedina `bearingbracket 1(31 .boltedf toa channel member 165- extending' `transversely;betvveen the trays. andsupported at its .outer ends in anyf'suitable'frame- AWork 166.

and these anti-friction bearings mustrbe adequately protectedby cover plates 164 Vandthe like for preventing the entrance of `sand-.into

these bearings. r`.I t-Willibe observed4 from Figure y10 that the deflecting skirt members 14.9 serve to deflect kthe sandfalling fromeach tray 142 outwardly'beyondthe bearings 164g` Mounted on? each of these shafts i's aplurality of mixing blades 167 each .of Whichblades is supportedbetween the halves oty a split clamp 168'Which clamps over'theshaftf 161. The blades are setvat different angular positionsabout the'shaft 161, andthe blades' arel given such pitch that their netv effect is to heap the sand over and simultaneously the-re- Withto move the sandeither inwardly or out,-

' Wardly across the surface of the tray,'d`epend ing upon which tray they are coactigngfwithf Thatis tosay, theactio-n ofthefblades above r.. -eachtraylfll Willbe to graduallyjyvork the `V Vsand outwardly toward the outer periphery ofthe tray and the action of the bladesabove d each tray 142 Will be to Work the sand inwardtical alinement.

mately mix and agitate the sand.

' As shown in Figure'l, the outer end of each shaft 161 carries-a belt pulley171, and these pulleys are all disposed in substantially verfmultiplicity of belts =1172 are trained Sover these pulleys, .aslshown inr this figure, so that all pulleysarerotated siv mult-aneously.V The bottom 'shaft' v161?- also carries an outer pulley 17 Sover which passes abelty 17tleading up to a single pulley 175 onA an upper countershaft 176. `flargepulley,

177 on this second countershaftisconnected through a. belt 178 With a pulley 179o`n the Y j irst countersh'aft y158; Thus, through thev drive ltransmitted to this counte rshaft.from*y the motorv 153, all of the mixingf'devices will l lrefl'erably, anti-friction bear?v ings are employed at boththe outer and innerl bearings 162 and 1611,rv as, shown Ain Figure 10,

rotated," simultaneously Av vith the rotation *Y 'of the several trays.

" The; sprinkler head l11 is suitably supportl v, `ed fabove the toptray 1411a so that Vthe vsand-is sprinkled immediatelyafter its precipitation on the top tray. VThe pipeline l181 connectingjrto this sprinkler head leads up to a point adjacent fthemold" forming zone A-vvhere1t provided With a control vvalve 182 Whichtliemolden can manipulate to'V controlfthe,

1 lill-ing the' molds, the molderjA finds thatthef sand is toowet or'too dry, he can, tvithoutlinfv convenience, regulate ithe Water supply-to vmoistenthe lsand-to theproperdegree. f *The conveyor'chamber lll-has its inleten'd disposed in immediate proximity to the edge' oftheflower tray 141", anda chute 1831ex` tends from this chamber above thelevel of* the loiveiftra'y so as `toproperly direct the sand*l Vdeflected vtherefrom dow-nintojxthe `chamber 44:.. lt' is opportunefto remarkaty this point that intliecase of the mixing device t2`for this lower tray-,141, the one ontvvo outermost 'blades are omitted as shovvnin Fig.`9 so that the sand/Will not bepushefd'folf" this tray but Will accumulate in an outer ridge thereon .in readiness to-be deflected oli by the rake Ll5.' The raleeis pivotedl at 184` to a bar 1-85 having' vertical pivotal movement" around a 'pivot E186 fat its other.` end'.

The verticali swingingr movementv4 vo tthis barj 185 permits the raleloto rise and fall, the

rake'normallyl restingunder its ovvn'yveiglit directly against the topl of the vdisk 141".

'l-hel rake isadapted to besvvung to diiferentl angularpositions for controllingthe rate of"r loe dischargel into vthe conveyor chamber 14. Y'

connected'to'theiake and Which'is operative ftd swing the same around-itsl pivot 1811" to control theradial depth of sand deflected off` the lower tray.,y The rod187 has connection through actuatin'g'l 'linkage v118.7 with a controlmember 188 disposedA inl close proximity to the molder ati the moldbforming ZoneAj` 'through a controlrod 187vvhieh is pivotally l v.Itthe rate of feedto the molding machine4 is too fast or too slow, the .,molder, lby simply manipulating the control member `188, can

properlyV regulate the rate of'feed for the. `1 1 5f111 i most elicientoperationof the mold formingy apparatus., A

the? bottom! of; the conveyor chamber 111 and comprises-1a multiplearm spider 189 rnountedI on-.th'e shaitlll; Blades V192 are detachably bolted to the arms of the spider, whereby... i

these blades maybe renewed in theevent of Wear. Theshaft 191i extends through: open-v ings in the 'sidewalls oft-he chamberll`r and The'sand impellertl is disposed yadjacent is journaled;inbeaiings 193 suitably supporti edfvo'utside ot this chamber. This shaft isf" connectedfthijougha vcoupling- 1941 directly to f iaothe armatureshaftV ofv an electric motor 195,

the sand impeller beingI thereby driven at a relatively high speed,

The sand is pitched. by this sand impellcr down into the lower boot i? of the bucket conveyor 48, as before described. This bucket conveyor is ot any suitable design, compi-isili!V an emlless belt or chain 4.L96 carrying space-,1i buckets lll. rlhe speed of this bucket conveyor such that the sand will be pitched from the upper end oit the conveyor casing all) into the vertical chute 5l without dropping any appreciable quant-ity oi sand down into the boot -l-T.

The sand rannning or ,sand slinging inachine 's oi the type known the Boardslef-lipcr machin and the supply of sand to this macaine and operation need not be descri;l yd as this type ot machine is woll known in the art.

As previously described, the mold Ytiasln-i are lilled o a grating through which the spilled and stricken oil' sand can'tall. The sand carrier and conditioner is cisposed directly below this mold forming :lione A4 so that this sand falling through the grating 54; will drop directly upon the top tray of the unit 3-, from whence it will again be con- \f'e \ged through the ensuing portion oi tho cycle back to the sand ramming machine 53.

The power drive ot the bucket conveyor i8 may be ,trom a separate electric motor and a cooperating speed reducing unit, or this bucket con eyor may be mechanically connected so as to be driven trom the impeller shaft l9l.

The electric motor for operating the sand rannning machine is generally controlled through a switch embodied in the handle ot the sand proecting arm, through which handle the sand projectin nozzle is swung to different parts oi the mold. I contemplate placin the circuit oit the electric motor 195 (and ot the electric motor 'for driving the bucket conveyor, where such separate drive is employed) under the control et this same switch, so that the ct of interrupting the operation ot the sand rannning machine, temporarily, will also interrupt the feed of sand to the ramming m a chino.

In conclusion, it will be apparent that the sand will be conducted through all ot the steps oi its conditioning cycle in a comparatively uniform thin stratum o stream and is subjeiieted to imiitorm treatment, so that all parts ot the sand will be directly acted upon, quick y cooled. and intimately mixed in the conditioning thereof. For example, the wa.- ter added to the san( is brought into immediate Contact will practically all portions ot' the .rand so that it f notnccessary to delay subsequent use ot the .und over a considerable time period 'in order to allow the water to 1L ermeate uni'lormly through the sand. Also, by retaining` the sand in a thin stratum or in small masses there is no opportunity 'for the sand to pack. The dissipation of the heat absorbed by the sand from the molten metal during its prior use is a part ci' the conditioning cycle, and it is to be noted that the repeated aeration ot' the sand that occurs during its intimate mixing, and while it is in a comparatively thin stratum or stream, quickly dissipates the heat, and avoids the delay in the reuse of the sand which has hereto- .tore been entailed due to the cooling period, after mixing, required by other processes of sand conditioning. `Whenever it is necessary to add more clay to the sand tor additional binder, this can be introduced on the top tray ot the. conditioning unit where it will first be moistened and thereafter thoroughly mixed with the sand in the subsequent cutting and mixing steps performed by the multiple mixing devices 42.

It a magnetic separator is employed for removing particles of the casting metal from the sand, this separator, preferably an electron'iagnet, may be located at any preferred point in the cycle where the sand stratum is comparatively thin, such as above the upper stretch ot the conveyor belt 37.

In the appended claims wherein I refer to the steps and apparatus for treating the sand, I have used the term conditioning in its broadest meaning as denoting either the adding ot water, or the adding ot' clay to the sand, or the mixing of the sand, or the cooline; of the sand, or the screening thereof, or all of these steps taken collectively.

While I have shown certain preferred methods and apparatus for carrying out my invention, it will be understood that such methods and apparatus are merely exemplary and can be varied widely without departing from the broad scope of the invention.

lNhat I claim as my invention and desire to secure by Letters lDatent, is

l. In apparatus for conditioning molding sand, the combination ot' a series of superposed impertorate trays all rotating together, and means for mixing the sand on said trays and ttor causing it to 'fall successively between said trays.

2. In apparatus for conditioning molding sand, the combination ot a plurality ot superposed trays all rotating together, and means tor mixing the sand on said trays and tor causing it to tall successively downwardly through the series oit trays.

3. In apparatus tor conditioning molding sand, the combination olf a plurality of superposed trays all rigidly connected together, means tor mixing the sand on said trays and for causing it to move progressively downward through the series ot trays, and means ior causing relative movement between said trays and said lirst named means about a substantially vertical axis.

4. In apparatus for conditioning molding raifairal .the sand-radially of` Sadrtays forv dropping 5, Vln apparatusffotiooidtonng ooo.loinsv N sand, the combination ,o a seriesofj superposedytraysall rotating toget11er,a nd mint ling apparatus ktor'mrong;.,tloo..,Sand on Seid f 1oy trays and folvoausingtlo sand tomovo in# 'War'clly and ogut'w'ardly of said trays for dropf ping from onetray to the next,V

' l. '16.;1nZ apparatusfor .conditioning mo-loing' sand; the ooinbinatou' ,of ia plurality,otuperposod rotatingtlays, and-mixing dovi'oos engaging with lthesandon .each ofsaid trays;

" `said.mixing vjlevices. oausingsaid sand Ito Vmore..inward.1yand.. outwardly oflsa-d trays for dropping fromtheinner andouterpe-l riphoros thoroofi 7. In Sand conditioning apparatus,the oom- .binationoff al revolving supporting lmember 7 .for .conveyinga bed of sand,.a rotating lmixi oausing relativo movemontbotwoenoaid triomf ging member. extending. transversely ooroSS the path-f .of Lmovement of -.Soid, Supporting 'memberl for mixing thev sand, andjmeansffor bers. g, .11 a8: ,In ,Sarioloondtonng ppamtllsftho. Com-5 @mation Zoff-a rotating supporting. member. --for .Supporting a bodfofsood, a mixing' mom. ber. for mixing .the sandrotatng; about on 1,axisat an angloto thoaxis of saidfsupporting member, ,andA means/ for .pausing rrelatiye transationalymotlon between the .bedof sand Y .and Vsaidno1 Xangln,oloobw ,11n sand, .conditioning yoolnbi nation ofv a lsuppgaritmg surfaee supporting abejd of Sand,` a mxlngmombor rotating about; anjaXisr l substantiallyj parallel-'to f said. supporting surface for .mixing thosaod, zand ,meansufor roauslng. .relativo .rotatlonol vmotion between ,the bed oi sandand'the axis Aof mixingmembr. f

Vmembers for causing the sand 'to fall p rogreaV siveljy from one. offsaid members; tothe next :in theicondtonngftherootl. .11, ,In `sandConditoning r.apparatus, the Acombination of superposed5-rotatingcarriers rotating. aboutl one. axis?, ond-rotating mixing devices rotating abouti another axis for HiX-f, ;ingthe sand 'While moving onfsaidoariiera. .Y 12.'1112V apparatus )for-oondltionug and kvthe molds to the polntk ofsubsequentnge 1n' handlingv molding sand, the oomjbnation ,o i a moving :supporting memberforgsupportng a `bed of; sand, a mixing1mg-m berg` for-miXing-jthe sandand: liawingoperatngmovement about "an axis extendingfsubstantially'parallel with -saidi supportingimember, 'means forA causing y-relatiye movement between @said members, a

agata the.

1 0. In sand.` oonditioningjapparatus, `the l combination .ofy a plurality .'of. i superposed `su oortin :membersmountedorrotationt l iabgilt asu stantialljyertioal axis and means fsmd frame struc-tureevolvesv sulprtfl'lg movable relatively .totali of, said supporting U leirculafran and a-piulgalayofrollorsengag;

f is."

.f :ll'anflloe1"7 moans for deflootng tho :Sand'irom said supporting member into said Chamber,

a' conveyorsfor `convey, ngthe.sand toar point fof-use, and impelling meansfforfprojeoting thesandffomisaid ohainblertosad conveyor.;

zof

Y., 13: -flnapparatus for conditioning alidhtnr-k 'il idling moldinggsand, the Joombnationfof a moving sand carry-ing surface, means for {mixing thesand tl1ereon,j'and adjustablev y t means-rondlscharging varlablequantitliesof sand :from said carrying ,surface after,v the oompletionof the mxingloperation thereon.

n 12141:. :In apparatus for oonditionngand han- 'ailing molding` sand, the ombinationljof -a horizontally `rotatingl sand Carryingv surface,

means for mixing thej ,.tliereon, deflect-V 1ng means -for dlsoharging the `sand `rorn s aidsurfaoe,fand remoteoperating means lo# A cated 'adjaoent the point of use of the sand for adjusting said ,delecting means.

:115. Sand oonditioningapparatus lof tlie i class desoribedooniprising a series of super` posed traysadapted to carry the sandinits conditioning operations3sa frame, structure supporting s'aidtrays,a1oentral pivotfor said 1 frame structure, a circular. rjailon. said iframek structure, a plurality. of rollers onwhiehsaid rail. tracks, a Circular :rack onaid' frame struoturaand ajgearlineshng with sad'raek l 16.l A sand oonditioningunitoftheqolas 1.1

lfor rotating'witllsaid operating, -1

desoribed, oomprisingg a4 series of superpos'ed; i

trays adapted to 1 oarry,,tlie, sand/duringwthe perforlnance"' lof. conditioning:-.1 operations thereon, a l:traine V structure supporting-said .100

trays, aball and socket central pivot for Q said.4

i frame structure, Ea oiroulttl railonsa'd iframe -struoture,gaplurality o frollers on which said n 'rail tracks, adjustable#supporting brackets v for 'raisingv and lowering said. rollers,`- aoirob @11.05 y lar raokfjonsaid frame strut-iure, andfaffgear meshing with said rackfofro'tatingfsaidunit.

'17. A sand conditioning machine oomp-ris-QW Lingo plutoltyiofiSuPPoSodtfftydaptd Y11o .l

to supp ort the 's a iframe stru'otfufre'oarryl ingsa-id trays, a Central pivot"around which means or'said f amejstruotureoomprisinga unit.

ous ymotionthrough `asanfd yconditi ning yolel,

, 12o( l fmovlngtho Sand Wlth asnlostantla vl oontlllu.- 4 f eXtendingfl'OiIl the pointl of dumpingfrom-- the-formation lof newtmolds.Screeningltiie Cil while the sand is in continuous motion in said cycle. Y

19. rlf'he method of handling and conditioning sand for foundry use which comprises moving the sand with a continuous motion through a conditioning cycle extending from the point of dumping from the molds baclf; to the point of subsequent use in the formation of new molds, screening the sand while in continuous motion in said cycle, and passing the sand downwardly over a series of superposed rotating conditioning surfaces vfor tempering, cutting and cooling the sand in its continuous motion through said conditioning cycle.

20. 'In sand conditioning apparatus, the combination of a series of su perposed rotating trays adapted to support beds of sand thereon, and mixing means engaging the sand on said trays for moving the same to the inner and outer peripheries of the trays, the inner and outer peripheries of said trays extending in alternating overlapping relation whereby the sand drops from the inner periphery of one tray to the next lower tray and from the outer periphery of said lower tray to the next succeeding tray.

2l. In sand conditioning apparatus, the combination of a series of superposed rotating trays adapted to support beds of sand thereon, rotating shafts extending across the upper surfaces of said trays, and blades on said shafts operative to mix the sand on said trays and to move the same to the peripheries of the trays for dropping to the next lower tray.

22. In apparatus for conditioning molding sand, the combination of a series of superposed rotating trays, means for feeding the sand thereto, mixing means cooperating with said trays for moving the sand transversely across the trays for dropping from tray to tray, means for conveying the conditioned sand from said trays to a mold forming Zone, spray means for supplying water to the sand on said trays, and control means actuable from said mold forming Zone for controlling said spray means.

23. In apparatus for conditioning molding sand, the combination of a hopper adapted to receive the sand after dumping from the molds, a conveyor belt traveling through the lower portion of said hopper, a rotating screen into which the sand is discharged from said conveyor belt, a series of superposed rotating trays adapted to receive the sand from said rotating screen, means for mixing the sand on said trays and for causing the same to fall from tray to tray, and means for conveying the sand from said series of trays to a mold forming zone.

24. In a sand conditioning device of the class described, the combination of central supporting means, a plurality of superposed trays all carried on said central supporting means, bearing means for said device, means for rotating all of said trays, and means for conditioning the sand carried on said trays.

25. A sand conditioning device of the class described comprising means, a plurality of superposed trays all secured to said central supporting means for simultaneous rotation, bearing means for said device, means for rotating said trays, and means for conditioning the sand carried on said trays and for causing the sand to fail progressively from one tray to the next.

26. In apparatus for conditioning molding sand, the combination of means for supplying water to the sand, a series of imperforate superposed trays all rotating together, and means for mixing the moistened sand on said trays and for causing it to fall successively between said trays.

27. In apparatus for conditioning molding sand, the combination of means for introducing water into the molding sand, a series of superposed rotating trays, and mixing apparatus moving relatively to all of said trays for mixing the moistened sand on said trays, and for causing' the sand to move inwardly and outwardly on said trays for dropping froin one tray to the next.

28. In sand conditioning apparatus, the combination of superposed trays rotating about a substantially'vertical axis, and rotary mixing devices adapted for rotation about another axis and operating to mix the sand on said trays.

29. In sand conditioning apparatus, the combination of a plurality of superposed trays rotating about a substantially vertical axis, and rotary mixing devices adapted for rotation about other axes at an angle to said substantially vertical axis, and operating to mix the sand on said trays and to move the sand transversely across the trays for falling from one tray to the next.

30. In sand conditioning apparatus, the combination of a horizontally rotating supporting member for conveying a bed of sand, a shaft extending across the top of said bed of sand at an angle to the path of movement of said supporting member, and a plurality of rotary mixing devices mounted on said shaft for mixing the sand.

3l. In sand conditioning apparatus, the combination of a plurality of superposed rotating trays each adapted to support a quantity of sand thereon, a plurality of shafts each disposed above one of said trays and extending at an angle to the path of movement of the sand supported thereon, and a plurality of rotary mixing devices mounted on said shafts for mixing the sand on said trays.

32. In apparatus for conditioning and handling molding sand, the combination of a plurality of superposed trays for supporting vthe sand, a plurality of mixing members rotating relatively to all of said trays for mixcentral supporting 1 ing thesandonsaid trays, means forcausf ing relativemovement between said trays and said mixing members, aconveyor kfor, conveying thesand to a point ofuse, and means for to said conveyor.

deiecting the sand from the lowermost'tray `33. Ink apparatus for conditioning and and handlingmolding vsa'nd,fthe combination of a A plurality of superposed rotating trays for supporting the sandindierent beds, avmix-L ing member for mixing the sand, vmeans for p causing relative movement between said mixini member and all of said-trays, means for i ecting the ysand lfromtlielowermost tray intosaid chamber, a conveyor'for conveying;

the sand to yap'ointof use, and impelling i 'means for projecting the sand from ,said

chamber to said conveyon 'i t v. 34. In apparatus for handling and condltioning molding sand wherein the sand isr moved substantially' continuously ina conf ,Y

ditioning cycle extending from the pointof dumping from the molds back to the point of subsequent use-in the formation of new molds,

't screening meansfreceiving' the [sandffrom theI combination of conveyingmeans for con" p veyingthe sand fromrsaid dumping point,

said conveying means," a pluralityof con ditioning surfaces receiving lthe sand from" said 'screening' means and` supporting-the sand in ,distributed beds,v means ,for mixing. the sand in said beds andfor causing it VtoV Vfallpro'gressively from one bed-toganother, f and conveying means yfor conveying the sand n from said bedsfbackto the point of subse-V V quent usein the :formation of new molds.

' 35. The herein described method which comprises v'taking the'V sand after dumping` from the molds,;transferr-ing it to the upperf most one of a plurality of superposed vrotat-V ing-surfaces, on which surfaces the sand is distributed in relatively shallow beds, dropping the sand from one surface down to the 'i next for aerating the sand,vengaging the beds of sand on said rotating surfaces with mixing devices to'turn the sand over and to intimate- ,y -k i ly mix it, all while in continuousmotion on saidsurfaces, and returning the conditioned sand to the mold forming zonefor usefin l making up new molds.

MAX ,sKL'ovsKn y 

